Chlorotrimethylsilane → 7-(bromomethyl)-2,2-dimethyl-3H-1-benzofuran

HRID 727167Notes

Reaction equation

HRID 727167 reaction equation
[Br-:1].[Li+].C[Si](Cl)(C)C.[CH3:8][C:9]1([CH3:20])[CH2:13][C:12]2[CH:14]=[CH:15][CH:16]=[C:17]([CH2:18]O)[C:11]=2[O:10]1>C(#N)C.C(OCC)C>[CH3:8][C:9]1([CH3:20])[CH2:13][C:12]2[CH:14]=[CH:15][CH:16]=[C:17]([CH2:18][Br:1])[C:11]=2[O:10]1

Participants

6

Reactant 3

HCID 6397ChlorotrimethylsilaneHCID 82050Lithium BromideHCID 2795472(2,2-Dimethyl-2,3-dihydro-1-benzofuran-7-yl)methanol

Product 1

HCID 42719367-(bromomethyl)-2,2-dimethyl-3H-1-benzofuran

Reagents, catalysts & solvents 2

HCID 3283Diethyl EtherSolventHCID 6342AcetonitrileSolvent2×

Procedure

Under a nitrogen atmosphere, a mixture of 8.7 grams (0.1 mole) of lithium bromide in 100 mL of acetonitrile is stirred, and 13.5 grams (0.125 mole) of trimethylsilyl chloride is added. Upon completion of addition, a solution of 8.9 grams (0.05 mole) of 2,3-dihydro-2,2-dimethylbenzofuran-7-ylmethanol in 50 mL of acetonitrile is added. Upon completion of addition, the reaction mixture is warmed to reflux, where it is stirred for about 18 hours. After this time the reaction mixture is cooled to ambient temperature and then is taken up in 200 mL of diethyl ether. The mixture is then washed with 25 mL of water and then with 25 mL of an aqueous solution saturated with sodium chloride. The organic layer is then dried with magnesium sulfate and filtered. The filtrate is concentrated under reduced pressure to a residue, yielding 2,3-dihydro-2,2-dimethylbenzofuran-7-ylmethyl bromide.

Workup

  1. additionUpon completion of addition
  2. additionUpon completion of addition
  3. temperaturethe reaction mixture is warmed
  4. temperatureto reflux
  5. stirringwhere it is stirred for about 18 hours
  6. washThe mixture is then washed with 25 mL of water
  7. dry with materialThe organic layer is then dried with magnesium sulfate
  8. filtrationfiltered
  9. concentrationThe filtrate is concentrated under reduced pressure to a residue

Sources & evidence

ORD record
ord-894e28eac1c54dccba787ba1056089ff
Source dataset
uspto-grants-1998_01
Patent number
US05712281

Reaction notes

Loading…